Electrolysis issues with coolant

[MOLON LABE]

Since going through two heater cores in the last couple of years and discovering that the problem is electrolysis I want to make sure it doesn't happen again.
I think I found the main cause. A bare braided ground wire laying on the metal heater tube coming out of the back of the intake manifold. It had rubbed a bare spot over time on the tube.
My question is, what's the best way to check for electrolysis, where do I check for it and are there any other common areas or problems known on a 1990 GMC Suburban 5.7 4x4 other than the one described above.
Thanks

 

[Roz]

i ground mine in many places. i am a ground nut. just tac a few wires in places that dont look grounded well. dont take much of a wire. i use a dremmel and clean off the area to metal sink the ground and cover it with rubber cement well. i dont have any probs. also use decent coolant. there is a min to use to prevent coolant rot. somethin like 10% (not sure)

 

[AKbigsub]

http://www.radcapproducts.com/radcap.html

 

[Roz]

hhmmm wonder how well it works

 

[AKbigsub]

hhmmm wonder how well it works

Works great! We were working on a '87 Trans Am that had this problem. It ate the head gaskets on a new motor we installed. I researched the problem and found that the dissimilar metals (aluminum, iron, copper etc.) compunded the problem. We installed ground wires everywhere and the problem still existed (we were measuring the current in the coolant using a DMM). I found the RAD Cap and installed one. This did not stop the current flow but allowed the sacrificial anode on the cap to be eaten instead of the engine parts. It worked so well, we became a distributor for RAD Cap and sold tons of them. I have since moved and no longer work there. However, due to this thread reminding me, I will be ordering a RAD Cap for all my vehicles!

 

[MarcS]

we were measuring the current in the coolant using a DMM

Start pulling fuses til the current stops to narrow down the bad circuit.

Almost lost my boats outdrive because of electrolysis. It can be a real PIA.

 

[AKbigsub]

The electrolosis is not due to a circuit feeding into the cooling system, it is due to the dissimilar metals of the system working in conjunction with the coolant. It produces its own electricity.

 

[roadnotca]

Use distilled water.

 

[Bubba Ray Boudreaux]

On top of everything else that has been said, to check you can dip a voltmeter into the coolant. There's some numbers that will tell you good/bad/indifferent, but it's been so long that I would have to look it up.

 

[81K5GUY]

Use distilled water.

smart man!! I had this same problem in a chevy Kodiak rollback and replaced it with distilled water and never had to replace the heater core again.I replaced 4 in a year before that!

 

[opfor2]

Use a DVM, place the positive in the radiator coolant and hook the negative to the neg on the battery, set the DVM to the lowest DC setting and read the DVM. Anything more that 0.03 volts you have a problem. Remember that most causes is due to improperly grounded add on components. So check all grounds and as stated before, start removing fuze's until the DVM shows no voltage and then you've found your circuit thats leaking voltage. Also poor cooling system maintenance will cause electrolysis. Use fresh coolant and use distilled water and this will usually eliminate electrolysis.

 

[roadnotca]

smart man!! I had this same problem in a chevy Kodiak rollback and replaced it with distilled water and never had to replace the heater core again.I replaced 4 in a year before that!

tip-o-the-hat Sir.

 

[MarcS]

The electrolysis is not due to a circuit feeding into the cooling system, it is due to the dissimilar metals of the system working in conjunction with the coolant. It produces its own electricity.

Yes, but stray electrical currents will accelerate the corrosion. A bad battery charger 3 boats down from mine caused my hydraulics to corrode and chunks missing from my outdrive.

I doubt you can measure current flow with a DMM, might be wrong, but I would think under "normal galvanic" conditions the current flow would be micro or nano-amps. I guess it would depend on the different materials and the electrolyte though.